cella

or naos

Enclosed body of a temple (as distinct from the portico), in which the image of the deity was housed. In early Greek and Roman architecture it was usually rectangular, with an entrance at one end; the side walls were often extended to form a porch. In larger temples the cella was sometimes open to the sky. In the Byzantine architectural tradition, the naos is the area of a central-plan church where the liturgy is performed.

Find more information on cella. Upgrade to Britannica Online for more on cella.